They usually come out after the rains and you can spot them in bushland around Perth: mushrooms, truffles, discs, caps and other fungi in all sorts of weird shapes, sizes and brilliant colours.
Now during the winter months you're also likely to spot another species: fungi hunters carrying their notebooks, cameras with big lenses, GPS units and specimen containers.
They're members and trained volunteers with the Perth Urban Bushland Fungi Project, a group which is part of an ongoing science venture to find and record as many of the estimated 140,000 species of fungi in WA as they can.
On their outings they walk slowly through the bush, peering and prodding gently at leaf litter and around fallen branches, even using DNA technology to identify their discoveries.
Their finds can include the foul-smelling stinkhorn fungus found in Kings Park that attracts flies and relies on them to pass on its spores.
Or the dog poo fungus which looks like … well, you get the idea!
Or the mysterious ghost fungus, which glows in the dark.
Dr Neale Bougher is a mycologist and researcher with the Department of Environment and Conservation and one of the organisers of the Perth Urban Bushland Fungus Project based at the State Herbarium.
'We've recorded more than 5,000 records of fungi in the Perth area', he says.
'That includes more than 500 unique species. In many cases, we give them names and we don't know what their names are because in some cases they've never been described in science.'
But he says that's just scratching the surface of what's out there in the bush.
'I estimate that in WA we might have up to 140,000 species of fungi and that's about 10 times more than the number of vascular plants. Unfortunately we only know about 5 to 10 per cent of those.'
Dr Bougher says the key to finding fungi is to walk slowly in the bush and you don't need to go far.
'Sometimes we only walk 10 metres or so in the whole morning and we might pick up - like yesterday - 32 species in about an hour in one spot in Kings Park. When we see them, we photograph them and record their location on a GPS and any associated plants nearby. That's important to know, because many of our fungi are partnered with plants that help those plants grow.'
Fungi are neither plants nor animals, yet Dr Bougher says they play a crucial role in native ecosystems and keeping the bush healthy. They are also an important source of food for insects and some animals, such as Australia's rarest species, the Gilbert's potoroo.
He says the Botanic Gardens and Parks Authority, which manages Kings Park and Bold Park in City Beach, is leading the way in recognising the importance of fungi.
'We've raised awareness to the point where it's almost becoming unacceptable not to consider the three F's - flora, fauna and fungi.'
He believes fungi are such an important part of an area's ecosystem it should be included in legislation and just as baseline studies are carried out to determine an area's vegetation, they should also be done for fungi.
'For example, the mining industry is obligated to survey for plants and animals, but at the moment they're not obligated to do that for fungi', he says.
Dr Bougher says more than 2000 people have taken part in the Perth Urban Bushland Fungi Project and its bushland excursions since it started in 2004.
Last year, the project was a finalist in the WA Science Awards.
To find out more about Perth's unique fungi, you can visit the project website which includes a downloadable field guide with colour photos of the fungi discovered so far - Fungi of the Perth Region and Beyond.